Decisions, dopamine and degeneracy in complex biological systems

The neurobiological and computational analysis of value-based decision-making rests
within the domain of neuroeconomics which has the goal of providing a biological
account of human behavior relevant to both natural and social sciences. This review
proposes a framework to investigate different aspects of the theoretical and molecular
neurobiology of decision-making. In order to learn how to make good decisions the
brain needs to compute a separate value signal that measures the desirability of the
outcomes that were generated by its previous decisions. The framework presented
here combines aspects of current ideas relating to information processing by the
hippocampal formation and how these relate to the phasic midbrain dopaminergic
firing that occurs in response to the spatial and motivational aspects of rewarding
events in the environment. The activities of hippocampal ensembles are considered to
reflect a continuous updating process for attended experiences, defining both regular
and irregular stimuli, environments and actions, which are rapidly encoded as
schemas into pre-existing knowledge bases.